Devices, systems, and methods for reshaping a heart valve annulus

ABSTRACT

Devices, systems, and methods employ an implant that is sized and configured to attach to the annulus of a dysfunctional heart valve annulus. In use, the implant extends across the major axis of the annulus above and/or along the valve annulus. The implant reshapes the major axis dimension and/or other surrounding anatomic structures. The implant restores to the heart valve annulus and leaflets a more functional anatomic shape and tension. The more functional anatomic shape and tension are conducive to coaptation of the leaflets, which, in turn, reduces retrograde flow or regurgitation. The implant improves function to the valve, without surgically cinching, resecting, and/or fixing in position large portions of a dilated annulus, or without the surgical fixation of ring-like structures.

RELATED APPLICATIONS

[0001] This application claims the benefit of co-pending U.S. patentapplication Ser. No. 09/666,617, filed Sep. 20, 2000 and entitled “HeartValve Annulus Device and Methods of Using Same,” which is incorporatedherein by reference. This application also claims the benefit of PatentCooperation Treaty application Ser. No. PCT/US 02/31376, filed Oct. 1,2002 and entitled “Systems and Devices for Heart Valve Treatments,”which claimed the benefit of U.S. Provisional Patent Application SerialNo. 60/326,590, filed Oct. 1, 2001, which are incorporated herein byreference. This application also claims the benefit of U.S. ProvisionalApplication Serial No. 60/429,444, filed Nov. 26, 2002, and entitled“Heart Valve Remodeling Devices;” U.S. Provisional Patent ApplicationSerial No. 60/429,709, filed Nov. 26, 2002, and entitled “Neo-LeafletMedical Devices;” and U.S. Provisional Patent Application Serial No.60/429,462, filed Nov. 26, 2002, and entitled “Heart Valve LeafletRetaining Devices,” which are each incorporated herein by reference.

FIELD OF THE INVENTION

[0002] The invention is directed to devices, systems, and methods forimproving the function of a heart valve, e.g., in the treatment ofmitral valve regurgitation.

BACKGROUND OF THE INVENTION

[0003] I. The Anatomy of a Healthy Heart

[0004] The heart (see FIG. 1) is slightly larger than a clenched fist.It is a double (left and right side), self-adjusting muscular pump, theparts of which work in unison to propel blood to all parts of the body.The right side of the heart receives poorly oxygenated (“venous”) bloodfrom the body from the superior vena cava and inferior vena cava andpumps it through the pulmonary artery to the lungs for oxygenation. Theleft side receives well-oxygenation (“arterial”) blood from the lungsthrough the pulmonary veins and pumps it into the aorta for distributionto the body.

[0005] The heart has four chambers, two on each side —the right and leftatria, and the right and left ventricles. The atria are theblood-receiving chambers, which pump blood into the ventricles. A wallcomposed of membranous and muscular parts, called the interatrialseptum, separates the right and left atria. The ventricles are theblood-discharging chambers. A wall composed of membranous and muscularparts, called the interventricular septum, separates the right and leftventricles.

[0006] The synchronous pumping actions of the left and right sides ofthe heart constitute the cardiac cycle. The cycle begins with a periodof ventricular relaxation, called ventricular diastole. The cycle endswith a period of ventricular contraction, called ventricular systole.

[0007] The heart has four valves (see FIGS. 2 and 3) that ensure thatblood does not flow in the wrong direction during the cardiac cycle;that is, to ensure that the blood does not back flow from the ventriclesinto the corresponding atria, or back flow from the arteries into thecorresponding ventricles. The valve between the left atrium and the leftventricle is the mitral valve. The valve between the right atrium andthe right ventricle is the tricuspid valve. The pulmonary valve is atthe opening of the pulmonary artery. The aortic valve is at the openingof the aorta.

[0008] At the beginning of ventricular diastole (i.e., ventricularfilling)(see FIG. 2), the aortic and pulmonary valves are closed toprevent back flow from the arteries into the ventricles. Shortlythereafter, the tricuspid and mitral valves open (as FIG. 2 shows), toallow flow from the atria into the corresponding ventricles. Shortlyafter ventricular systole (i.e., ventricular emptying) begins, thetricuspid and mitral valves close (see FIG. 3)—to prevent back flow fromthe ventricles into the corresponding atria—and the aortic and pulmonaryvalves open—to permit discharge of blood into the arteries from thecorresponding ventricles.

[0009] The opening and closing of heart valves occur primarily as aresult of pressure differences. For example, the opening and closing ofthe mitral valve occurs as a result of the pressure differences betweenthe left atrium and the left ventricle. During ventricular diastole,when ventricles are relaxed, the venous return of blood from thepulmonary veins into the left atrium causes the pressure in the atriumto exceed that in the ventricle. As a result, the mitral valve opens,allowing blood to enter the ventricle. As the ventricle contracts duringventricular systole, the intraventricular pressure rises above thepressure in the atrium and pushes the mitral valve shut.

[0010] The mitral and tricuspid valves are defined by fibrous rings ofcollagen, each called an annulus, which forms a part of the fibrousskeleton of the heart. The annulus provides attachments for the twocusps or leaflets of the mitral valve (called the anterior and posteriorcusps) and the three cusps or leaflets of the tricuspid valve. Theleaflets receive chordae tendineae from more than one papillary muscle.In a healthy heart, these muscles and their tendinous cords support themitral and tricuspid valves, allowing the leaflets to resist the highpressure developed during contractions (pumping) of the left and rightventricles.

[0011] In a healthy heart, the chordae tendineae become taut, preventingthe leaflets from being forced into the left or right atria and everted.Prolapse is a term used to describe this condition. This is normallyprevented by contraction of the papillary muscles within the ventricle,which are connected to the mitral valve leaflets by the chordaetendineae. Contraction of the papillary muscles is simultaneous with thecontraction of the ventricle and serves to keep healthy valve leafletstightly shut at peak contraction pressures exerted by the ventricle.

[0012] II. Characteristics and Causes of Mitral Valve Dysfunction

[0013] In a healthy heart (see FIG. 4), the dimensions of the mitralvalve annulus—when measured septal (S)- to -lateral (L), as well as fromposterior commissure CP to anterior commissure CA—create an anatomicshape and tension such that the leaflets coapt, forming a tightjunction, at peak contraction pressures. Where the leaflets coapt at theopposing medial and lateral sides of the annulus are called the leafletcommissures, and are designated in FIG. 4 and in other Figures asCP(denoting the posterior commissure) and CA (denoting the anteriorcommissure).

[0014] Valve malfunction can result from the chordae tendineae (thechords) becoming stretched, and in some cases tearing. When a chordtears, the result is a leaflet that flails. Also, a normally structuredvalve may not function properly because of an enlargement of or shapechange in the valve annulus. This condition is referred to as a dilationof the annulus and generally results from heart muscle failure. Inaddition, the valve may be defective at birth or because of an acquireddisease.

[0015] Regardless of the cause (see FIG. 5), mitral valve dysfunctioncan occur when the leaflets do not coapt at peak contraction pressures.As FIG. 5 shows, the coaptation line of the two leaflets is not tight atventricular systole. As a result, an undesired back flow of blood fromthe left ventricle into the left atrium can occur. This condition iscalled regurgitation.

[0016] In some cases (see FIG. 6), the leaflets do not form a tightcoaptation junction because the dimensions of the mitral valve annulus,measured from commissure to commissure—CP to CA—and/or septal tolateral—S to L—change. The changed dimensions no longer create theanatomic shape and tension in which the leaflets coapt at peakcontraction pressures.

[0017] Comparing a healthy annulus in FIG. 4 to an unhealthy annulus inFIG. 6, the unhealthy annulus is dilated and, in particular, theseptal-to-lateral distance is increased. As a result, the shape andtension defined by the annulus becomes less oval (see FIG. 4) and moreround (see FIG. 6). This condition is called dilation. When the annulusis dilated, the shape and tension conducive for coaptation at peakcontraction pressures progressively deteriorate. Instead, at peakcontraction pressures, the leaflets do not coapt completely, and a gapforms between the leaflets. During ventricular systole, regurgitationcan occur through this gap. It is believed that the ratio between thecommissure distance and septal-to-lateral distance bears a relationshipto the effectiveness of leaflet coaptation. If the septal-to-lateraldistance increases, the ratio changes, and when the ratio reaches acertain value, regurgitation or the likelihood of regurgitation isindicated.

[0018] As a result of regurgitation, “extra” blood back flows into theleft atrium. During subsequent ventricular diastole (when the heartrelaxes), this “extra” blood returns to the left ventricle, creating avolume overload, i.e., too much blood in the left ventricle. Duringsubsequent ventricular systole (when the heart contracts), there is moreblood in the ventricle than expected. This means that: (1) the heartmust pump harder to move the extra blood; (2) too little blood may movefrom the heart to the rest of the body; and (3) over time, the leftventricle may begin to stretch and enlarge to accommodate the largervolume of blood, and the left ventricle may become weaker.

[0019] Although mild cases of mitral valve regurgitation result in fewproblems, more severe and chronic cases eventually weaken the heart andcan result in heart failure. Mitral valve regurgitation can be an acuteor chronic condition. It is sometimes called mitral insufficiency.

[0020] III. Prior Treatment Modalities

[0021] In the treatment of mitral valve regurgitation, diuretics and/orvasodilators can be used to help reduce the amount of blood flowing backinto the left atrium. An intra-aortic balloon counterpulsation device isused if the condition is not stabilized with medications. For chronic oracute mitral valve regurgitation, surgery to repair or replace themitral valve is often necessary.

[0022] To date, invasive, open heart surgical approaches have been usedto repair mitral valve dysfunction. During these surgical repairprocedures, efforts are made to cinch or resect portions and/or fix inposition large portions of the dilated annulus. During these surgicalrepair procedures, the annulus can be reshaped with annular orperi-annular rings or similar ring-like devices. The repair devices aretypically secured to the annulus and surrounding tissue withsuture-based fixation. The repair devices extend over the top and overmuch or all of the circumference of the annulus and leaflet surfaces.

[0023] A physician may decide to replace an unhealthy mitral valverather than repair it. Invasive, open heart surgical approaches are usedto replace the natural valve with either a mechanical valve orbiological tissue (bioprosthetic) taken from pigs, cows, or horses.

[0024] The need remains for simple, cost-effective, and less invasivedevices, systems, and methods for treating dysfunction of a heart valve,e.g., in the treatment of mitral valve regurgitation.

SUMMARY OF THE INVENTION

[0025] The invention provides devices, systems and methods that reshapea valve annulus. The devices, systems, and methods include an implantthat is sized and configured to rest near or within the leafletcommissures of a heart valve annulus. In use, the implant contacts andoutwardly displaces tissue to reshape the heart valve annulus. Theimplant, in use, may restore to the heart valve annulus and leaflets amore effective anatomic shape and tension. The more normal anatomicshape and tension are conducive to coaptation of the leaflets, which, inturn, reduces retrograde flow or regurgitation. The implant restoresfunction to the valve, without surgically cinching, resecting, and/orfixing in position large portions of a dilated annulus, or without thesurgical fixation of ring-like structures.

[0026] Other features and advantages of the invention shall be apparentbased upon the accompanying description, drawings, and claims.

DESCRIPTION OF THE DRAWINGS

[0027]FIG. 1 is a perspective, anterior anatomic view of the interior ofa healthy heart.

[0028]FIG. 2 is a superior anatomic view of the interior of a healthyheart, with the atria removed, showing the condition of the heart valvesduring ventricular diastole.

[0029]FIG. 3 is a superior anatomic view of the interior of a healthyheart, with the atria removed, showing the condition of the heart valvesduring ventricular systole.

[0030]FIG. 4 is a superior anatomic view of a healthy mitral valveduring ventricular systole, showing the leaflets properly coapting.

[0031]FIG. 5 is a superior anatomic view of the interior of a heart,with the atria removed, showing the condition of the heart valves duringventricular systole, and further showing a dysfunctional mitral valve inwhich the leaflets are not properly coapting, causing regurgitation.

[0032]FIG. 6 is a superior anatomic view of a disfunctional mitral valveduring ventricular systole, showing that the leaflets are not properlycoapting, causing regurgitation.

[0033]FIG. 7A is a side perspective view of an elastic implant sized andconfigured to rest within or near the leaflet commissures of adysfunctional heart valve annulus to reshape the annulus and improveleaflet coaptation.

[0034]FIGS. 7B to 7E are side perspective views of illustrativealternative configurations of the elastic implant shown in FIG. 7A.

[0035]FIG. 8 is a side anterior anatomic view of a mitral valve annulusin which the elastic implant shown in FIG. 7A has been implanted.

[0036]FIG. 9 is a superior anatomic view of a mitral valve in which theelastic implant shown in FIG. 7A has been implanted, showing the implantstretching the commissures to restore leaflet coaptation.

[0037]FIG. 10 is a side perspective view of another embodiment of anelastic implant sized and configured to rest within or near the leafletcommissures of a dysfunctional heart valve annulus to reshape theannulus and restore leaflet coaptation, the implant defining a closedannular structure.

[0038]FIG. 11 is a perspective anatomic view, taken from an anterior andslightly superior viewpoint, of a mitral valve in which the elasticimplant of the type shown in FIG. 10 has been implanted, showing theimplant stretching the commissures to restore leaflet coaptation, andalso showing the implant as hugging the annulus.

[0039]FIG. 12 is a perspective anatomic view, taken from an anterior andslightly superior viewpoint, of a mitral valve in which the elasticimplant of the type shown in FIG. 10 has been implanted, showing theimplant stretching the commissures to restore leaflet coaptation, andalso showing the implant as rising above the annulus.

[0040]FIGS. 13A to 13C are side perspective views of illustrativeembodiments of an elastic implant sized and configured to rest within ornear the leaflet commissures of a dysfunctional heart valve annulus toreshape the annulus and restore leaflet coaptation, the implant definingan open annular structure.

[0041]FIGS. 13D and 13E are side perspective views of illustrativeembodiments of an elastic implant sized and configured to rest within ornear the leaflet commissures of a dysfunctional heart valve annulus toreshape the annulus and restore leaflet coaptation, the implant definingan open annular structure that can be optionally closed.

[0042]FIG. 14 is a side perspective view of an elastic implant of theopen annular type shown in FIGS. 13D and 13E, showing how the mechanicalcharacteristics of the implant can be varied along its structure,surface area, and interface with the tissue.

[0043]FIG. 15A is a side perspective view of another embodiment of anelastic implant sized and configured to rest within or near the leafletcommissures of a dysfunctional heart valve annulus to reshape theannulus and restore leaflet coaptation, the implant defining a closedannular structure that can be symmetrically folded upon itself.

[0044]FIG. 15B is a side view of the implant shown in FIG. 15A whenfolded upon itself.

[0045]FIG. 15C is a perspective anatomic view, taken from an anteriorand slightly superior viewpoint, of a mitral valve in which the elasticimplant of the type shown in FIG. 15A has been implanted, showing theimplant stretching the commissures to restore leaflet coaptation, andalso showing the implant as hugging the annulus.

[0046]FIG. 15D is a side perspective view of another embodiment of anelastic implant sized and configured to rest within or near the leafletcommissures of a dysfunctional heart valve annulus to reshape theannulus and restore leaflet coaptation, the implant defining a closedannular structure that can be asymmetrically folded upon itself.

[0047]FIG. 15E is a perspective anatomic view, taken from an anteriorand slightly superior viewpoint, of a mitral valve in which the elasticimplant of the type shown in FIG. 15D has been implanted, showing theimplant stretching the commissures to restore leaflet coaptation, andalso showing the implant as hugging the annulus.

[0048]FIG. 16A is a side perspective view of an elastic implant of thetype shown in FIG. 10, showing an illustrative embodiment of tabstructures that serve to anchor and stabilize the implant in an annulus.

[0049]FIG. 16B is a side anterior anatomic view of a mitral valveannulus in which the elastic implant shown in FIG. 16A has beenimplanted.

[0050]FIG. 17A is a side perspective view of an elastic implant of thetype shown in FIG. 10, showing an illustrative embodiment of multiplecontact structures that serve to anchor and stabilize the implant in anannulus.

[0051]FIG. 17B is a side anterior anatomic view of a mitral valveannulus in which the elastic implant shown in FIG. 17A has beenimplanted.

[0052]FIGS. 18A and 18B are side perspective views of an elastic implantof the type shown in FIG. 10, showing illustrative embodiments offrictional struts that serve to anchor and stabilize the implant in anannulus.

[0053]FIG. 19 is a side perspective view of an elastic implant of thetype shown in FIG. 10, showing an illustrative embodiment of tissuein-growth surfaces that serve to anchor and stabilize the implant in anannulus.

[0054]FIGS. 20A and 20B are, respectively, a side perspective view andan anatomic view (when implanted) of an elastic implant sized andconfigured to rest within or near the leaflet commissures of adysfunctional heart valve annulus to reshape the annulus and restoreleaflet coaptation and also showing the implant as rising significantlyabove the annulus.

[0055]FIGS. 20B and 20C are, respectively, a side perspective view andan anatomic view (when implanted) of an elastic implant sized andconfigured to rest within or near the leaflet commissures of adysfunctional heart valve annulus to reshape the annulus and restoreleaflet coaptation, and showing the presence of one rail that hugs theannulus and another rail that rises above the implant to serve as amechanism that anchors and stabilizes the implant in the annulus.

[0056]FIG. 21 is a side elevation view of a tool for implanting anelastic implant in a valve annulus in a open heart surgical procedure toreshape the annulus and restore leaflet coaptation.

[0057]FIGS. 22A to 22F diagrammatically show a method of using the toolshown in FIG. 21 to install an elastic implant in a valve annulus toreshape the annulus and restore leaflet coaptation.

[0058]FIGS. 23A to 23C diagrammatically show a method of gainingintravascular access to the left atrium for the purpose of deploying adelivery catheter to place an implant in a valve annulus to reshape theannulus and restore leaflet coaptation.

[0059]FIG. 24 is a side elevation view of the distal end of the implantdelivery catheter shown in FIG. 23C, showing an elastic implant of thetype shown in FIG. 10 collapsed in a sleeve for deployment into the leftatrium in the manner shown in FIGS. 23A to 23C.

[0060]FIGS. 25A to 25E are diagrammatic perspective views of a methodfor manipulating the distal end of the implant delivery catheter shownin FIG. 24 to deploy an elastic implant of the type shown in FIG. 10into a valve annulus to reshape the annulus and restore leafletcoaptation.

[0061]FIG. 26 is a side view of the distal end of the implant deliverycatheter of the type shown in FIG. 23C, showing an elastic implant ofthe type shown in FIG. 10 collapsed in a sleeve for deployment into theleft atrium in the manner shown in FIGS. 23A to 23C, also and showingthe presence of a guide wire loop to aid in the deployment.

[0062]FIGS. 27A to 27I are diagrammatic views of a method for deployingan elastic implant of the type shown in FIG. 10 into a valve annuluswith the aid of a guide wire loop to reshape the annulus and restoreleaflet coaptation.

[0063]FIGS. 28A and 28B are perspective view of elastic implants of thetype shown in FIGS. 13B to 13E, showing the tethering of such implantsto one or more wire loops to aid in their deployment into a valveannulus to reshape the annulus and restore leaflet coaptation.

[0064]FIG. 29 is a side view of the distal end of the implant deliverycatheter of the type shown in FIG. 23C, showing a symmetrical foldableelastic implant of the type shown in FIG. 15A folded and collapsed in asleeve for deployment into the left atrium in the manner shown in FIGS.23A to 23C.

[0065]FIGS. 30A to 30D are diagrammatic views of a method formanipulating the distal end of the implant delivery catheter shown inFIG. 29 to deploy a symmetrically folded and collapsed elastic implantof the type shown in FIG. 15A into a valve annulus to reshape theannulus and restore leaflet coaptation.

[0066]FIGS. 31A to 31E are diagrammatic views of a method formanipulating the distal end of the implant delivery catheter shown inFIG. 29 to deploy an asymmetrically folded and collapsed elastic implantof the type shown in FIG. 15D into a valve annulus to reshape theannulus and restore leaflet coaptation.

[0067]FIG. 32 is a side view of the distal end of the implant deliverycatheter of the type shown in FIG. 23C, showing a symmetrical foldableelastic implant of the type shown in FIG. 15A tethered to a guide wireloop to aid in its implantation into a valve annulus to reshape theannulus and restore leaflet coaptation.

[0068]FIGS. 33A to 33D are diagrammatic views of a method formanipulating the distal end of the implant delivery catheter shown inFIG. 32 to deploy a symmetrically folded and collapsed elastic implantof the type shown in FIG. 15A into a valve annulus with the aid of aguide wire loop to reshape the annulus and restore leaflet coaptation.

[0069]FIG. 34 is a side elevation view of the distal end of the implantdelivery catheter of the type shown in FIG. 23C, showing a symmetricalfoldable elastic implant of the type shown in FIG. 15A tethered to twoguide wire loops to aid in its implantation into a valve annulus toreshape the annulus and restore leaflet coaptation.

[0070]FIGS. 35 and 36A to 36D are diagrammatic views of a method formanipulating the distal end of the implant delivery catheter to deploy asymmetrically folded and collapsed elastic implant of the type shown inFIG. 15A into a valve annulus with the aid of a separate guide wires toreshape the annulus and restore leaflet coaptation.

[0071]FIGS. 37A to 37C are diagrammatic views of the deployment asymmetrically folded and collapsed elastic implant of the type shown inFIG. 15A into a valve annulus with the aid of a wrapper or bag toreshape the annulus and restore leaflet coaptation.

[0072]FIG. 38 is a side perspective view of a plastically deformableimplant sized and configured to be expanded in situ to rest within ornear the leaflet commissures of a dysfunctional heart valve annulus toreshape the annulus and restore leaflet coaptation.

[0073]FIGS. 39A to 39C are diagrammatic views of the deployment of aplastically deformable implant of the type shown in FIG. 38 into a valveannulus with the aid of a mechanical expansion device.

[0074]FIGS. 40A to 40C are diagrammatic anatomic views of the deploymentof a plastically deformable implant of the type shown in FIG. 38 into avalve annulus with the aid of a balloon expansion device.

[0075]FIG. 41 is a diagrammatic view of a non-compliant balloon deployedinto a valve annulus for the purpose of assessing the size andmechanical properties of an implant for the annulus.

[0076]FIG. 42 is a side perspective view of a multi-functional elasticimplant sized and configured to rest within or near the leafletcommissures of a dysfunctional heart valve annulus to reshape theannulus and restore leaflet coaptation as well serve as a neo-leaflet toeither replace or supplement a damaged heart valve leaflet.

[0077]FIGS. 43 and 44 are side perspective views of a multi-functionalelastic implants sized and configured to rest within or near the leafletcommissures of a dysfunctional heart valve annulus to reshape theannulus and restore leaflet coaptation as well serve as a leafletretainer to prevent a native valve leaflet from being pushed into theatrium upon ventricular contraction.

[0078] FIGS. 45 to 47 are side perspective views of a multi-functionalelastic implants sized and configured to rest within or near the leafletcommissures of a dysfunctional heart valve annulus to reshape theannulus and restore leaflet coaptation as well serve as a leafletretainer to prevent a native valve leaflet from being pushed into theatrium upon ventricular contraction, the implants also including aframework that serves to help position and secure the implant in situ.

DETAILED DESCRIPTION

[0079] Although the disclosure hereof is detailed and exact to enablethose skilled in the art to practice the invention, the physicalembodiments herein disclosed merely exemplify the invention, which maybe embodied in other specific structure. While the preferred embodimenthas been described, the details may be changed without departing fromthe invention, which is defined by the claims.

[0080] I. Implants for Reshaping a Heart Valve Annulus

[0081] A. Overview

[0082]FIGS. 7A and 8 show an implant 10 sized and configured to restwithin or near a heart valve annulus. The implant is shown in a mitralvalve, and, in this arrangement, extends along the major (i.e., longest)axis above and/or along the valve annulus. The implant 10 is sized andshaped so that, in use, it applies a mechanical force along the majoraxis. The mechanical force serves to outwardly displace tissue (i.e., todisplace tissue away from the center of the annulus) to reshape theannulus. In the illustrated embodiment (on the mitral valve), themechanical-force serves to lengthen the long axis of the annulus and, indoing so, can reactively shorten in the minor (i.e. shortest) axis, aswell as correspondingly reshape other surrounding anatomic structures.It should be appreciated that, when situated in other valve structures,the axes affected may not be the “major” and “minor” axes, due to thesurrounding anatomy. It should also be appreciated that, in order to betherapeutic, the implant may only need to reshape the annulus during aportion of the heart cycle, such as during ventricular systoliccontraction. For example, the implant may be sized to produce small ornegligible outward displacement of tissue during ventricular diastolewhen the tissue is relaxed, but restrict the inward movement of tissueduring ventricular systolic contraction.

[0083] The mechanical force applied by the implant 10 restores to theheart valve annulus and leaflets a more normal anatomic shape andtension (see FIG. 9). The more normal anatomic shape and tension areconducive to coaptation of the leaflets during ventricular systole,which, in turn, reduces regurgitation. The implant 10 restores normalfunction to the valve, without surgically cinching, resecting, and/orfixing in position large portions of a dilated annulus or leaflets, orwithout the surgical fixation of ring-like structures.

[0084] As will be described in greater detail later, the implant 10lends itself to delivery to a targeted heart valve site bycatheter-based, intravascular techniques, under image guidance. Imageguidance includes but is not limited to fluoroscopy, ultrasound,magnetic resonance, computed tomography, or combinations thereof.Alternatively, the implant 10 can be delivered using conventional openheart surgical techniques or by thoracoscopic surgery techniques.

[0085] In its most basic form, the implant 10 is made—e.g., by bending,shaping, joining, machining, molding, or extrusion—from a biocompatiblemetallic or polymer material, or a metallic or polymer material that issuitably coated, impregnated, or otherwise treated with a material toimpart biocompatibility, or a combination of such materials. Thematerial is also desirably radio-opaque to facilitate fluoroscopicvisualization.

[0086] As FIG. 7A shows, the implant 10 includes a pair of struts 12joined by an intermediate rail 14. As FIG. 8 shows, the struts 14 aresized and configured to rest at or near the leaflet commissures. Itshould be appreciated that the leaflet commissures may not, andtypically are not, situated at geometrically opposite sides of theannulus (although for the purpose of illustration, they are shown thatway in the Figures). The position of the struts 12 can be selected toconform to an asymmetric morphology of the annulus, as is laterdescribed in connection with FIGS. 13A and 13B.

[0087] The rail 14 spans the struts 12. The rail 14 (like the struts 12)can take various shapes and have various cross-sectional geometries. Therail 14 (and/or the struts 12) can have, e.g., a generally curvilinear(i.e., round or oval) cross-section, or a generally rectilinear crosssection (i.e., square or rectangular), or combinations thereof.

[0088] In FIGS. 7A and 8, the implant is “elastic.” The rail 14 is sizedand configured to possess a normal, unloaded, shape or condition (shownin FIG. 7A), in which the rail 14 is not in compression and the struts12 are spaced apart farther than the anterior commissure to posteriorcommissure dimension of the targeted heart valve annulus. The materialof the implant is selected to possess a desired spring constant. Thespring constant imparts to the rail 14 the ability to be elasticallycompressed out of its normal, unloaded condition, in response toexternal compression forces applied at the struts. The rail 14 is sizedand configured to assume an elastically loaded, in compressioncondition, during which the struts 12 are spaced apart a sufficientlyshorter distance to rest in engagement with tissue at or near theleaflet commissures (see FIG. 8).

[0089] When in its elastically loaded, compressed condition (see FIG.9), the rail 14 exerts opposing forces to the tissues at or near thecommissures through the struts 12, tending to outwardly displace tissueand stretch the annulus along its major axis, which also typicallystretches the leaflet commissures, shortens the minor axis, and/orreshapes surrounding anatomic structures. The implant thereby reshapesthe valve annulus toward a shape more conducive to leaflet coaptation.

[0090] An elastic implant can be made, e.g., from superelastic alloy,such that the implant can be elastically straightened and/or folded tofit within a catheter or sheath during deployment, and will regain itsshape upon deployment (this characteristic will be described in greaterdetail later).

[0091] Desirably, the elasticity of the implant 10 itself, along withthe elasticity of the valve tissue, ensure that the implant 10 can bepositioned in the valve under a state of net compression and thus remainanchored without the use of sutures, adhesives, or other fixationmaterials, i.e. which is called compressive anchoring. The implant 10may itself deform elastically, although not necessarily so, but thecharacteristic of the implant 10 being elastically deformable may helpto maintain compressive anchoring. If the implant 10 does not deformelastically or does so only slightly, the implant 10 relies on tissueelasticity to keep the implant anchored.

[0092] As FIGS. 7A to 7E and 8 show, and as will be described in greaterdetail later, the struts 12 may carry other structures or mechanisms 16to further enhance the anchorage and stabilization of the implant in theheart valve annulus. The mechanisms 16 may be located below the plane ofthe annulus, to engage infra-annular heart tissue adjoining the annulusin the ventricle, and/or be located at or above the plane of theannulus, to engage tissue on the annulus or in the atrium.

[0093] The spring constant of the implant may be selected to be greaterthan the spring constant of adjoining tissue. Alternatively, the springconstant of the implant may be selected to approximate the springconstant of adjoining tissue, thereby providing compliance to allow theimplant 10 to adapt to tissue morphology during use. The spring constantof the implant 10 may vary along the length of the rail 14, so that someportions of the rail 14 are stiffer or more compliant than otherportions of the rail 14.

[0094] In an alternative arrangement, the implant 10 may be formed froma plastically deformable material. In this embodiment, the implant 10 ismanufactured in a normally collapsed condition. The implant 10 isexpanded in situ into an in use condition within the annulus, e.g., byan inflatable body (e.g., balloon) or by a suitable mechanical device(e.g., a scissorjack). The use and deployment of a plasticallydeformable implant will be described in greater detail later, after thestructure, deployment, and use of elastic implants are described.

[0095] B. Illustrative Elastic Implant Configurations

[0096] An elastic implant 10 having the characteristic just describedcan take various forms and configurations. The following describesvarious illustrative arrangements.

[0097] 1. Collapsible Annular Implants

[0098] The implants 10 in FIGS. 7A to 7C comprise a single rail 14spanning the distance between the struts 12. As shown in FIGS. 7D and10, an implant 10 can include more than a single rail 14, imparting anormally closed, annular shape to the implant. As will be described ingreater detail later, an implant 10 of this type can be conveyed to animplantation site, e.g., within a catheter or sheath, in a collapsed,straightened condition (with the rails 14 collapsed side-by-side) Whendeployed from the catheter or sheath, the implant 10 springs open toassume the normally closed, annular shape shown in FIGS. 7D and 10.

[0099] In the arrangement illustrated in FIG. 10, the implant 10includes two rails 14 spanning the struts 12. The shape andconfiguration of the rails 14 can be varied, depending upon the desiredorientation of the rails 14 with respect to the annulus itself. Forexample, in FIG. 11, the two rails 14 are shaped and configured so that,when implanted, the rails 14 follow the circumferential path of theannulus and rest in generally the same plane as the annulus. Thisimplant can be characterized as “hugging” the annulus. In the exampleshown in FIG. 12, the two rails 14 are shaped and configured so that,when implanted, the rails 14 follow the circumferential path of theannulus, and also rise above the plane of the annulus. This implant 10can be characterized as “riding above” the annulus. An implant 10 that“rides above” the annulus can extend close to the annulus (as FIG. 12shows) or rise significantly above the annulus toward the dome of theatrium as FIGS. 20A and 20B show. As FIGS. 20C and 20D show, an implant10 can include a rail 14A that hugs the annulus and a rail 14B thatrides above the annulus and contacts a heart wall, serving as amechanism 16 that orients and stabilizes the implant.

[0100] When the rail or rails 14 of a given implant follow thecircumferential contour of the annulus, either at or above the plane ofthe annulus, the rails 14 rest out of the way of blood flow though thevalve and may reduce hemolysis or thrombosis.

[0101] As FIGS. 13A to 13E show, the rails 14 of a given annular implant10 can be interrupted to impart a normally open annular (“hemi”) shapeto the implant 10. As will be described in greater detail later, animplant 10 of this type also can be conveyed to an implantation site,e.g., within a catheter or sheath, in a collapsed, straightenedcondition, and then deployed to assume the open, annular shape shown inFIGS. 13A to 13E.

[0102] In FIG. 13A, the open annular shape is configured so that, whenimplanted, the implant 10 hugs the annulus. In FIG. 13B, the openannular shape is configured so that, when implanted, the implant ridesabove the annulus. FIGS. 13C and 13D show another style of open annularimplant, one that hugs the annulus (FIG. 13C) and the other that ridesabove the annulus (FIG. 13D). In this arrangement, the interrupted rail14 includes interlocking hooks 18 that can be coupled, if desired, toclose the annulus of the implant 10 (see FIG. 13E). In FIG. 13E, theinterlocked implant 10 is configured to ride above the annulus.

[0103] As FIGS. 13A and 13B show, the struts 12 need not be placed atdiametrically opposite sides of the rail or rails 14. The commissures ofa given valve annulus may not be at geometrically opposite sides of theannulus. Accordingly, the position of the struts 12 may be selected toconform to an asymmetric morphology of the annulus. The struts 12 may beused to simply locate the implant 10 in the valve, imparting little orno force on their own. In this arrangement, the annulus reshaping forcesemanate from the rail or rails 14 above the commissures.

[0104] The implant possesses a spring constant that approximates thespring constant of tissue, making the implant more accommodating to themovement of the tissue. As FIG. 14 shows, a given rail or rails 14 caninclude undulations or the like to impart regions having differentspring constants and/or mechanical properties along the length of therail 14. Alternatively, or in combination, the cross-sectional widthand/or thickness and/or geometry of a given rail 14 need not be uniform,but can vary along the length of the rail 14 to impart regions ofdifferent spring constants and/or mechanical properties. For example, inFIG. 13A, the region of the continuous rail 14 between theasymmetrically placed struts 12 may be thickened or thinned to impartdifferent mechanical properties to achieve the desired shape changingobjectives.

[0105] 2. Foldable Elastic Annular Implants

[0106] The implants 10 shown in FIGS. 15A to 15E comprise more than asingle rail 14, imparting a normally closed, annular shape to theimplant. Unlike the normally closed, annular implant 10 shown in FIG.10, the rails 14 of the implants 10 shown in FIGS. 15A to 15E includecusps 20. The cusps 20 permit the implants to be resiliently foldedalong their minor (transverse axis) axis—with the cusps 20 occupying thefold—without permanently deforming the implant (see FIG. 15B). As willbe described in greater detail later, an implant 10 of this type can beconveyed to an implantation site, e.g., within a catheter or sheath, ina folded as well as collapsed condition, and then deployed to assume thenormally closed, annular shape shown in FIG. 15A, as FIG. 15C shows. Asbefore explained, the shape and configuration of the rails 14 can bevaried so that, when deployed, the implant hugs the annulus or ridesabove the annulus.

[0107] In FIG. 15A, the cusps 20 are symmetric, being formed on eachrail 14 equidistant to the struts 12. In FIG. 15A, the struts 12 arealso shown symmetric as to height above the rail 14. FIG. 15D shows thatthe cusps 20 need not be symmetric in either respect. As will bedescribed in greater detail later, this asymmetry permits a stepwise,staggered deployment of the implant, in which the parts of the implantare deployed one at a time in succession—e.g., one strut, then one cusp,then another strut, and then the other cusp—until the implant assumesthe closed, annular shape shown in FIG. 15D, as FIG. 15E shows.

[0108] 3. Fixation of Implants

[0109] As before stated, the struts 12 can include other structures ormechanisms 16 to further enhance the anchorage and stabilization of theimplant in the heart valve annulus. These structures or other mechanisms16 can comprise, e.g., loops, pads, barbs, vertical legs, orcircumferential legs, or other anchoring structures below, at, and/orabove the valve plane. The structures and mechanisms 16 desirablyincrease the surface area of contact between the struts 12 and tissueadjoining the annulus. The structures and mechanism 16 desirably relysolely or partly on the valve and neighboring anatomic structures toanchor and fix the position of the implant in the annulus and resist itsmigration out of the annulus. Implant fixation can also assist in theachieving the desired coaptation of the leaflets and to resist upwardmovement or eversion of the leaflets during the cardiac cycle.

[0110] For example, in the embodiment shown in FIGS. 7A and 8, the rails14 carry four struts12, two supra-annular (contacting tissue on theatrial side of the valve) and two infra-annular (contacting tissue onthe ventricular size of the valve). The struts 12 are separated by athin spine that curves away from the struts 12 to avoid contact with thecommissures themselves, so as not to interfere with the opening andclosing of the valve.

[0111] As shown in FIG. 7A, the struts 12 may be cushioned to increasetraction, decrease erosion, and improve their interaction with the valveannulus. In addition, the struts 12 may be coated, covered, orimpregnated with a tissue growth promoting material. The rails 14spanning the struts 12 functions to exert compressive forces on theannulus. The struts 12 are secured by the compression forces created bythe rail's interaction with the valve annulus. The struts 12 assure thatthe implant is positioned correctly in situ, because they will only seatwhen positioned at or near the commissures of the valve.

[0112] The struts 12 may be sized and shaped in various ways. FIGS. 7B,7C, and 7D show various embodiments with alternative designs for thestruts 12. As another example, in FIG. 7E, the supra-annular struts 12are somewhat larger than the infra-annular struts 12 to improve theanatomical fit of the device in situ.

[0113] In the embodiment shown in FIGS. 16A and 16B, the struts 12 cancarry flat infra-annular tissue contacting pads 26, located below theplane of the valve annulus. The pads 26 rest on outwardly bowedextensions below the commissures, applying holding forces upon the heartwalls. The pads 26 can take the form of flat surfaces, as FIGS. 16A and16B show. Tissue penetrating barbs 28 (shown in phantom lines in FIG.16B) may enhance the effect of the compression forces to fix thelocation of the implant.

[0114] As FIGS. 17A and 17B show, the struts 12 can extend in anundulating fashion below the plane of the valve annulus, to create aseries of infra-annular contact surfaces 30 between the implant and theheart walls below and adjoining the annulus. The series of contactsurfaces 30 increase the points of contact between the implant andtissue below the annulus. These multiple points of contact 30 areadditive to the contact between the implant and tissue at or near thecommissures themselves. In FIGS. 17A and 17B, additional struts and/orbarbs or similar anchoring surfaces (such as shown in FIGS. 16A and 16B)are not shown associated with the contact surfaces, but they could beincluded, if desired.

[0115] As FIGS. 18A and 18B show, the implant can include infra-annularfrictional struts 32 located below the level of the annulus. Theinfra-annular frictional struts 32 engage tissue of the heart wallsbelow and adjoining the annulus. The struts 32 resist migration of theimplant out of the annulus. As FIG. 18A shows, the frictional struts 32can be placed in a single level immediately below the commissures, or(as FIG. 18B shows) the struts 32 can be arranged in multiple levelsbelow the commissures.

[0116] As FIG. 19 shows, the struts 12 and/or the rails 14 can includetissue in-growth surfaces 34. The surfaces 14 provide an environmentthat encourages the in-growth of neighboring tissue on the implant. Oncein-growth occurs, the implant 10 becomes resistant to migration ordislodgment from the annulus. Conventional in-growth materials such aspolyester fabric can be used.

[0117] Any fixation mechanism or structure may, if desired, be combinedwith an adhesive or like material to further secure the implant.

[0118] II. Deployment of Elastic Implants for Reshaping a Heart ValveAnnulus

[0119] The various implants as just described lend themselves toimplantation in a heart valve annulus in various ways. They can beimplanted, e.g., in an open heart surgical procedure. Alternatively,they can be implanted using catheter-based technology via a peripheralvenous access site, such as in the femoral or jugular vein or femoralartery, or alternatively by thoracoscopically through the chest or bymeans of other surgical access through the right atrium.

[0120] A. Open Heart Surgical Procedures

[0121]FIG. 21 shows a tool 40 for deploying an elastic implant 10 of thetype generally described in an annulus of a heart valve in an opensurgical procedure. FIGS. 22A to 22F diagrammatically show the steps ofan open surgical procedure for deploying the implant 10 in a mitralvalve annulus using the tool 40 shown in FIG. 21.

[0122] The tool 40 includes a scissors-action mechanism 42 comprising anoperating end 46 and a handle end 48. The operating end 46 includesprongs 44 that can be moved apart and together by manipulation of thehandle end 48 (see FIGS. 22A and 22B). The prongs 44 are sized andconfigured to mate with deployment apertures 50 formed on the struts 12of the implant 10 (shown in FIG. 21). The deployment apertures 50 arealso shown in the implants in preceding FIGS. 10 to 19, which can belikewise be deployed using the tool 40.

[0123] In using the tool 40, the scissors-action mechanism 42 ismanipulated to spread the prongs 44 apart (see FIGS. 22A and 22B), sothat they can be mated in the apertures 50 of the implant 10. Thescissors-action mechanism 44 is manipulated to bring the prongs 44together, thereby applying force to the struts 12 to place the implant10 in a compressed condition (see FIG. 22C).

[0124] With the tool 40 holding the implant 10 in this condition, thetool 40 and implant 10 are introduced through an open surgical approachinto the left atrium. The tool 40 places the implant 10 within themitral valve annulus (see FIG. 22D). As shown in FIG. 22D, the annulusis shown to have a dimension of D1. This dimension D1 is not conduciveto leaflet coaptation, and regurgitation is occurring. It is the purposeof the surgical procedure to repair this dysfunction by reshaping theannulus with the implant 10.

[0125] The scissors-action mechanism 42 is manipulated to spread theprongs 44 apart until the struts 12 of the implant 10 rest within ornear the commissures of the mitral valve (see FIG. 22E). At this pointin the procedure, the dimension D1 of the annulus remains unchanged. Thetool 40 is withdrawn, freeing the prongs 12 from the apertures 50 (seeFIG. 22F). The elastic unloading of the implant 10 displaces and spreadsthe valve tissue apart, achieving a new dimension D2 for the annulus,which is larger than D1. The new dimension D2 is conducive to leafletcoaptation. The implant 10 has reshaped the annulus to restore valvefunction.

[0126] B. Illustrative Catheter-Based Intra-Vascular Procedures

[0127] 1. Linear Deployment of Elastic Implants

[0128] FIGS. 23 to 25 show a representative embodiment of a percutaneouscatheter-based linear deployment of an unfolded elastic implant 10 ofthe type shown in FIGS. 7 to 14.

[0129] Percutaneous vascular access is achieved by conventional methodsinto the femoral or jugular vein. As FIG. 23A shows, under imageguidance, a catheter 52 is steered through the vasculature into theright atrium. A needle cannula 54 carried on the distal end of thecatheter is deployed to pierce the septum between the right and leftatrium. As FIG. 23B shows, a guide wire 56 is advanced trans-septallythrough the needle catheter 52 into the left atrium. The first catheter52 is withdrawn, and (as FIG. 23C shows) under image guidance, animplant delivery catheter 58 is advanced over the guide wire 56 into theleft atrium into proximity with the mitral valve. Alternatively, theimplant delivery catheter 58 can be deployed trans-septally by means ofsurgical access through the right atrium.

[0130] The implant delivery catheter 58 carries a sheath 60 at itsdistal end (see FIG. 24). The sheath 60 encloses an elastic implant 10of a type shown in FIGS. 7 to 14. The implant 10 is constrained in acollapsed, straightened condition within the sheath, as FIG. 24 shows.The sheath 60 can be sized and configured to be withdrawn (e.g., bysliding it proximally), to free the implant 10. Free of the sheath 60,the elastic implant 10 will expand. Alternatively, a flexible push rod62 in the catheter 58 can be used to expel the implant 10 from thesheath 60, with the same result. Desirably, the strut 12 on the trailingend of the implant 10 is folded within the sheath 60 to reduce thecollapsed profile and facilitate the expansion of the implant 10 oncefree from the sheath 60.

[0131] As FIG. 25A shows, under image guidance, the strut 12 on theleading end of the implant 10 is freed from the sheath 60 and seatedretrograde in the posterior commissure of the valve annulus. Anchoringstructures or mechanisms associated with the strut are also placed intodesired contact with adjoining tissue below and/or above the plane ofthe annulus. As FIG. 25B shows, the delivery catheter 58 maintains forceon the leading strut 12 within the posterior commissure, as the sheath60 is withdrawn in line with the coaptation line in aposterior-to-anterior direction along the coaptation line. As shown inFIG. 25B, the delivery catheter 58 may need to dip down retrograde belowthe plane of the leaflets to maintain sufficient force on the leadingend of the implant while the trailing end is freed from the sheath 60.However, as shown in FIG. 25C, the delivery catheter 58 may be sized andconfigured to have the column strength sufficient to maintain force onthe leading strut without passage below the leaflet plane.

[0132] Progressively freed from the sheath 60, the elastic implant 10shapes and seats (as FIGS. 25B/C and 25D shows), until the trailingstrut 12 unfolds and seats within the anterior commissure (see FIG.25E). The implant can also be positioned or repositioned under imageguidance within the left atrium using a catheter-deployed graspinginstrument.

[0133] 2. Guide Loop Deployment of Unfolded Elastic Implants

[0134]FIGS. 26 and 27A to 27I show another embodiment of an implantdelivery catheter 58 that can be used to deploy a folded elastic implant10 of the type shown in FIGS. 7 to 14 within the left atrium.

[0135] In this embodiment, as in the previous embodiment, the implantdelivery catheter 58 includes a sheath 60 that constrains the implant 10in a collapsed, straightened condition for passage into the left atrium(see FIG. 26). The sheath 60 is sized and configured to be withdrawn(e.g., by sliding it proximally), to free the implant for expansionwithin the left atrium, or a push rod 62 can be used to eject theimplant from the sheath 60. To create a desired profile, one or bothstruts can be folded against the body of the implant within the sheath60.

[0136] Unlike the previous embodiment, a metallic, fiber, or polymerguide wire 64 is looped through the deployment apertures 50 on thestruts 12 of the implant 10 prior to the insertion of the implant 12into the sheath 60. The legs of the resulting guide wire loop 66 arepassed out the proximal end of the sheath 60 for manipulation, as willnow be described.

[0137] In use, the implant delivery catheter 58 is introducedtrans-septally into the left atrium in the manner previously described.With the distal end of the catheter 58 positioned above the valveannulus (see FIG. 27A), and prior to withdrawal of the sheath 60, bothlegs of the guide wire loop 66 are advanced distally in tandem throughthe sheath 60 to advance the loop 60 beyond the deployment apertures 50and out the distal end of the sheath 60. The guide wire loop 66desirably carries radio-opaque markers 68 to aid in fluoroscopicvisualization. The markers 68 identify a desired distance between themand the distal end of the sheath 60, marking a space in which theimplant 10 can freely expand without contacting tissue or anatomicstructures within the atrium. Guided by the markers 68, the loop 66 canbe dropped into the annulus a desired distance beyond the distal end ofthe sheath 60, as FIG. 27A shows.

[0138] With the loop 66 positioned in the desired way within theannulus, the sheath 60 can be withdrawn to free the implant 10 forexpansion (see FIG. 27B). While tethered to the guide wire loop 66, theimplant 10 opens within the left atrium—first one strut, then theother—as the sheath 60 is withdrawn, as FIGS. 27C and 27D show.

[0139] Once the implant 10 is fully free of the sheath 60 and expanded,both legs of the guide wire loop 66 can be advanced proximally in tandemthrough the sheath 60 (see FIG. 27E). The wire loop 66 applies force tothe struts 12 and brings them together (see FIG. 27F). This places theimplant 10 in a compressed, elastically loaded condition. Proximaladvancement of the legs of the wire loop 66 also draws the implant 10 inthis condition snuggly against the distal end of the catheter 58 forgreater control, as FIG. 27F shows.

[0140] With the implant 10 tethered to the catheter 58 in this condition(see FIG. 27G), the catheter 58 can be advanced under image guidance toplace the implant 10 within the annulus. Manipulation of the catheter 58will bring the struts of the implant into desired alignment. Subsequentdistal advancement of the legs of the wire loop 66 (see FIG. 27H) allowsthe struts of the implant 10 to be elastically unloaded and brought intocontact with the surrounding tissue. Anchoring structures or mechanismsassociated with the struts 12 can also be placed into desired contactwith adjoining tissue below and/or above the plane of the annulus. Thelegs of the wire loop 66 can be manipulated to pull the struts 12together and/or allow them to separate, until the desired orientationand tissue contact in and about the annulus are achieved.

[0141] Once desired orientation and tissue contact are achieved for theimplant 10, one leg of the wire loop 66 can be pulled to release theimplant from the guide wire 64 (see FIG. 27I). The implant 10 is allowedto fully unfold and seat within the annulus.

[0142] A guide loop 66 can be used to deploy open annular implants aswell as closed annular implants. As shown in FIG. 28A, a single guideloop 66 can be threaded through an open annular implant 10 of the typeshown in FIG. 13B. Or, as shown in FIG. 28B, two guide wire loops 66Aand 66B can be threaded through an inter-locking implant of the typeshown in FIGS. 13D and 13E. In this arrangement, the first guide wireloop 66A can be manipulated to position the struts 12 of the implantwithin the annulus, as just described. The second guide wire loop 66Bcan be separately manipulated to pull the rails 14 together forinterlocking, once the struts rest in a desired manner in thecommissures.

[0143] 3. Deployment of Folded Elastic Implants

[0144]FIGS. 15A to 15E show elastic implants 10 that can be folded aboutcusps 20. As FIG. 29 shows, the folding allows the implant 10 to beconveyed into the left atrium within a sheath 60 of an implant deliverycatheter 58 with a delivery profile that not only constitutes aside-to-side collapsed condition—which minimizes the delivery profilediameter—but also constitutes a lengthwise folded condition—whichminimizes the delivery profile length.

[0145]FIGS. 30A to 30D illustrate the deployment of a symmetricallyfolded elastic implant 10 of the type shown in FIGS. 15A and 15B. Theimplant 10 is constrained in a symmetrically folded and collapsedcondition within the sheath 60, as FIG. 30A shows. In this condition,the struts 12 form the leading end of the implant. A push rod 62 in thecatheter 58 includes a gripping mechanism 70 that holds the foldedimplant 10 by the cusps 20. The push rod 62 is advanced to expel theimplant 12 from the sheath 60, both struts 12 first.

[0146] As FIG. 30B shows, under image guidance, the folded implant 10 isaligned with coaptation line generally equidistant from the commissures,with the struts 12 oriented to face the commissures (the deliverycatheter 58 has been previously introduced trans-septally into the leftatrium, as already described). Manipulating the push rod 62 advances theimplant 10, both struts first, from the sheath 60. Connecting the pushrod 62 to the implant 10 allows the implant 10 to be translated androtated and retracted during deployment. Freed from the sheath 60 (seeFIG. 30B), the implant 10 begins to unfold along the cusps 20, and thestruts 12 draw apart toward the commissures. Further advancement of thepush rod 62 frees more of the unfolding implant 10 from the sheath 60,until the struts 12 draw apart sufficiently to contact the commissures(as FIG. 30C shows). Prior to release of the cusps 20 from the grippingmechanism 70, the implant 10 can be manipulated to assure that anchoringstructures or mechanisms associated with the strut are placed intodesired contact with adjoining tissue below and/or above the plane ofthe annulus. The gripping mechanism 70 can then be activated (see FIG.30D), releasing the implant 10.

[0147]FIGS. 31A to 31E illustrate the deployment of an asymmetricallyfolded elastic implant 10 of the type shown in FIGS. 15D and 15E. Theimplant 10 is constrained in an asymmetrically folded and collapsedcondition within the sheath 60, as FIG. 31A shows. The grippingmechanism 70 holds one, but not both of the cusps 20. This is becausethe height of the cusps 20 above the rails 14 is also asymmetric. Thegripping mechanism 70 will couple to the taller cusp 20. The push rod 62can be advanced to expel the implant 10 from the sheath 60. Due to theasymmetry of the cusps 20, one of the struts 12 is positioned fordeployment before the other strut 12. Also due to the asymmetry of thecusps 20, the shorter cusp 20 is positioned for advancement out of thesheath 60 before the taller cusp 20 is released by the grippingmechanism 70.

[0148] As FIG. 31B shows, under image guidance, the folded and collapsedimplant 10 is aligned with coaptation line near one of the commissures(the delivery catheter 58 has been previously introduced trans-septallyinto the left atrium, as already described). Manipulating the push rod62 advances the implant 10 from the sheath 60. The leading strut 12 isfreed first (see FIG. 31B) and placed against the adjacent commissure.The implant 10 can be manipulated to assure that anchoring structures ormechanisms associated with the leading strut are placed into desiredcontact with adjoining tissue below and/or above the plane of theannulus. Further advancement of push rod 62 causes the implant 10 tounfold toward the opposite commissure. Continued advancement of the pushrod 62 frees more of the unfolding implant 10 from the sheath 60, untilthe trailing strut 12 contacts the opposite commissure (as FIG. 31Cshows). The implant 10 can be manipulated to assure that anchoringstructures or mechanisms associated with the trailing strut 12 areplaced into desired contact with adjoining tissue below and/or above theplane of the annulus. Further advancement of the push rod 62 frees theshorter cusp 12 from the sheath 60, and the implant 10 springs openalong this side (see FIG. 31D). The gripping mechanism 70 can then beactivated (see FIG. 31), releasing the taller cusp 12. The implant 10springs open in this direction. It can be seen that the. asymmetry ofthe implant 10 make possible a step-wise deployment of the implant 10,one component at a time, in the annulus.

[0149] 4. Guide Wire Assisted Deployment of Folded Elastic Implants

[0150] The use of one or more guide loops 66 or tethers to assist in thedeployment of unfolded elastic implants has been previously discussed.One or more guide loops 66 or tethers can likewise be employed to assistin the deployment of folded elastic implants of either symmetric orasymmetric types.

[0151] For example, as shown in FIG. 32, a metallic, fiber, or polymerguide wire 64 can be looped through the deployment apertures on thestruts of a folded symmetric or asymmetric implant 10 prior to thefolding and insertion of the implant 10 into the sheath 60. The legs ofthe resulting guide wire loop 66 are passed out the proximal end of thesheath 60 for manipulation.

[0152] In use (see FIG. 33A)—after the implant delivery catheter 58 isintroduced trans-septally into the left atrium in the manner previouslydescribed, and prior to activation of the push rod 62—both legs of theguide wire loop 66 are advanced distally in tandem through the sheath 60to advance the loop 66 beyond the deployment apertures and out thedistal end of the sheath 60. The loop 66 is placed within the annulus.

[0153] The push rod 62 is manipulated to free the folded implant 10 forexpansion (see FIG. 33B). The implant 10 opens while tethered to theguide wire loop 66. The loop 66 increases in diameter as the struts 12expand apart. The perimeter of the loop 66 will orient itself along thegreatest dimension of the annulus—which is the distance between thecommissures. The loop 66 thereby orients the implant 10 with thecoaptation line during implant 10 expansion. The legs of the loop 66guide the struts 12 to the commissures (as FIG. 33C shows).

[0154] Tethered to the catheter 58, the implant 10 is deployed in theannulus. The guide wire loop 66 maintains control of the strut spacingwithin the commissures during implant expansion.

[0155] Once desired orientation and tissue contact are achieved for theimplant 10, the gripping mechanism 70 can release the implant 10. Oneleg of the wire loop 66 can be pulled to release the implant 10 from theguide wire (see FIG. 33D). The implant 10 is allowed to fully unfold andseat within the annulus.

[0156] As FIG. 34 shows, a second guide wire loop 72 can also be passedthrough apertures on the cusps 20. This guide wire loop 72 can bemanipulated independently of the first guide wire loop 66, to controldeployment of the expanding implant 10 in the septal-to-lateraldimension. Simultaneous, although independent, control of the expandingimplant 10 can be achieved by manipulation of the first guide wire 66.

[0157] As FIGS. 35 and 36A to 36D show, separate metallic, fiber, orpolymer guide wires 92 can be individually threaded (without looping)through small holes on the struts of a folded symmetric or asymmetricimplant 10 prior to the folding and insertion of the implant 10 into thesheath 60 (see FIG. 35). The separate guide wires 92 are passed out theproximal end of the sheath 60 for manipulation.

[0158] In use (see FIG. 36A)—after the implant delivery catheter 58 isintroduced trans-septally into the left atrium in the manner previouslydescribed, and prior to activation of the push rod 62—the separate guidewires 92 are advanced distally in tandem through the sheath 60 and outthe distal end of the sheath 60. The ends of the wires 92 are placedwithin the annulus.

[0159] The push rod 62 is manipulated to free the folded implant 10 forexpansion (see FIG. 36B). The implant 10 opens while tethered to theseparate guide wires 92. The guide wires 92 will orient themselves alongthe major axis of the annulus—which is the distance between thecommissures, to orient the implant 10 with the coaptation line duringimplant 10 expansion. The guide wires 92 separately guide the respectivestruts 12 to the commissures (as FIG. 36C shows).

[0160] Tethered to the catheter 58, the implant 10 is deployed in theannulus. The guide wires 92 maintain control of the strut spacing withinthe commissures during implant expansion.

[0161] Once desired orientation and tissue contact are achieved for theimplant 10, the gripping mechanism 70 can release the implant 10. Theguide wires 92 can be pulled to release the implant 10 from the guidewires (see FIG. 36D). The implant 10 is allowed to fully unfold and seatwithin the annulus.

[0162] 5. Other Forms of Assisted Deployment of Folded Elastic Implants

[0163] The foregoing embodiments demonstrate that the unfolding of anelastic implant 10 can be controlled during deployment in either themajor axis dimension, or the minor axis (septal-to-lateral) dimension,or in both dimensions by means of guide wires. Other forms ofrestraining mechanisms can be used to control the unfolding of theimplant 10.

[0164] For example, as shown in FIG. 37A, the folded implant 10 can berestrained within a bag or wrapper 76 as the implant 10 is advanced fromthe delivery sheath 60. The bag or wrapper 76 restricts expansion of theimplant 10 beyond a selected point (e.g., 80% of full deployment),allowing the physician to attend to the important task of seating thestruts in the commissures before the implant 10 fully opens across theannulus. Once the implant 10 has been seated in the commissures andreleased from the delivery sheath 60 (see FIG. 37B), a ripcord 78coupled to the bag or wrapper 76 can be pulled, to release the bag orwrapper 76 from the implant 10 (see FIG. 37C). Freed from the bag orwrapper 76, the implant 10 completes its expansion, to achieve finalshaping and seating within the annulus. One or more guide wires can beused in combination with the bag or wrapper 76. The bag or wrapper 76can alternatively be sized and configured to tear away as a result ofthe implant 10 expanding beyond a given point, without the use of aripcord 78 or similar induced tearing mechanism. In another arrangement,the implant 10 can be enclosed within a shrink-wrap structure having ascore line. In these arrangements, the structure is sized and configuredto restrain expansion of the implant 10 until the implant 10 is advancedoutside of the delivery sheath beyond a given point, at which time thescore line parts or the material strength of the structure is exceeded,to open and fully release the implant 10.

[0165] III. Plastically Deformable Implants for Reshaping a Heart ValveAnnulus and Their Deployment

[0166] As previously described, the implant 10 may be formed fromplastically deformable material (see FIG. 38). The implant 10 includesstruts and one or more rails, as previously described. The implant 10 isdeployed by an implant delivery catheter 58 into the left atrium in anormally collapsed condition. In this arrangement, an implant deliverycatheter 58 can carry a mechanical expansion device 80, such as ascissorjack or the like (see FIGS. 39A to 39C), to expand theplastically deformable material of the implant 10 in situ within theannulus. Alternatively, an implant delivery catheter 58 can carry aninflatable body 82 (e.g., balloon) (see FIGS. 40A to 40C), to expand theimplant 10 within the annulus. During expansion, the plasticallydeformable implant 10 stretches the annulus to achieve a desired majoraxis size. Once expanded, the plastically deformable implant 10maintains the desired distance, thereby resisting contraction of theannulus. The plastically deformable implant 10 may include otherstructures or mechanisms to further anchor and stabilize the implant 10in the heart valve annulus.

[0167] IV. Ascertaining Implant Size and Resistance

[0168] The shape and structure of a heart valve such as a mitral valveand the neighboring anatomic structures are generally understood bymedical professionals using textbooks of human anatomy along with theirknowledge of the site and its disease or injury. Ranges of shapes anddimensions for a given implant are defined by the site to be treated.Precise dimensions for a given patient can be determined by X-ray, MRI,or CT scanning of the site to be treated prior to implantation of animplant.

[0169] A physician may also ascertain the size and resistance for agiven implant by the deployment of a non-compliant balloon gauge 84 inthe targeted annulus, as shown in FIG. 41. The balloon gauge 84 cancarry radio-opaque markers 86 so that dimensions of the annulus can bedetermined using imaging means and/or other forms of in situvisualization. The compliance and tension forces of the annulus can alsobe physically measured, by sensing and quantifying the resistance theballoon gauge 84 encounters during expansion in the annulus. Based uponthis data, and taking into account the physician's knowledge of the siteand its disease or injury, a physician can select a desired size andmechanical properties for the implant.

[0170] V. Multi-Functional Implants

[0171] Various embodiments of implants 10 have described the context ofreshaping a heart valve annulus. A given implant 10 having technicalfeatures suited for this function can also incorporate other technicalfeatures well suited for other functions.

[0172] By way of illustration, FIG. 42 shows an annulus remodelingimplant 10 in which the rails 14 are sized and configured to define apseudo-annulus. A neoleaflet element 88 comprising a fabric-coveredbridge structure is coupled to the rails. The neoleaflet element issized and configured to occupy the space of at least a portion of anative heart valve leaflet to provide a one-way valve function. Inresponse to ventricular diastolic pressure, the one-way valve functionassumes a valve opened condition within the pseudo-annulus. In responseto ventricular systolic pressure, the one-way valve function assumes avalve closed condition within the pseudo-annulus. The neoleaflet element88 serves to repair, replace, or supplement a damaged heart valve.

[0173]FIGS. 43 and 44 show an annulus remodeling implant 10 in which therails 14 are sized and configured serve as a pseudo-annulus. The implant10 includes a retaining structure 90 near or within the pseudo-annulusthat is sized and shaped to overlay at least a portion of one or morenative valve leaflets. The retaining structure 90 retains a native valveleaflet, keeping the valve leaflet from a retrograde flow condition,e.g., by being pushed into the atrium, i.e., eversion and/or prolapse.

[0174] As further examples of multi-functional implants, FIGS. 45 to 47shows an annulus remodeling implant 10 in which the rails furtherinclude a framework 38 (as previously described) to help position andsecure the device in situ. In FIGS. 45 to 47, the framework 38 alsoincludes a leaflet retaining structure 90, as just described.

[0175] While the new devices and methods have been more specificallydescribed in the context of the treatment of a mitral heart valve, itshould be understood that other heart valve types can be treated in thesame or equivalent fashion. By way of example, and not by limitation,the present systems and methods could be used to prevent or reduceretrograde flow in any heart valve annulus, including the tricuspidvalve, the pulmonary valve, or the aortic valve. In addition, otherembodiments and uses of the invention will be apparent to those skilledin the art from consideration of the specification and practice of theinvention disclosed herein. The specification and examples should beconsidered exemplary and merely descriptive of key technical; featuresand principles, and are not meant to be limiting. The true scope andspirit of the invention are defined by the following claims. As will beeasily understood by those of ordinary skill in the art, variations andmodifications of each of the disclosed embodiments can be easily madewithin the scope of this invention as defined by the following claims.

What is claimed is:
 1. An implant to reshape a heart valve annuluscomprising a body sized and configured to rest near or within a heartvalve annulus, including a portion of the body contacting and outwardlydisplacing tissue to reshape the heart valve annulus.
 2. An implant toreshape a heart valve annulus comprising a body sized and configured torest in net compression near or within a heart valve annulus, includinga portion of the body contacting tissue to displace tissue to reshapethe heart valve annulus.
 3. An implant to reshape a heart valve annuluscomprising a body sized and configured to rest in net compression nearor within a heart valve annulus, and spaced-apart struts appended to thebody to contact tissue near or within the heart valve annulus, thestruts being sized and configured to displace tissue as a result of thenet compression to reshape the heart valve annulus.
 4. An implant toreshape a heart valve having an annulus and leaflet commissurescomprising a body sized and configured to rest in net compression nearor within a heart valve annulus, and spaced-apart struts appended to thebody to contact tissue at or near the leaflet commissures, the strutsbeing sized and configured to displace tissue as a result of the netcompression to reshape the heart valve annulus.
 5. An implant to reshapea heart valve annulus comprising a body sized and configured to rest innet compression near or within a heart valve annulus, and spaced-apartstruts appended to the body to contact tissue near or within the heartvalve annulus, the struts being sized and configured to apply tension totissue as a result of the compression of the body to reshape the heartvalve annulus.
 6. An implant to reshape a heart valve having an annulusand leaflet commissures comprising a body sized and configured to restin net compression near or within the heart valve annulus, andspaced-apart struts appended to the body to contact tissue at or nearthe leaflet commissures, the structures being sized and configured toapply tension to tissue at or near the leaflet commissures as a resultof the compression of the body to shape and tension the heart valveannulus for leaflet coaptation.
 7. An implant according to claim 1 or 2or 3 or 4 or 5 or 6 wherein the body comprises an annular shape.
 8. Animplant according to claim 1 or 2 or 3 or 4 or 5 or 6 wherein the bodycomprises a closed annular shape.
 9. An implant according to claim 1 or2 or 3 or 4 or 5 or 6 wherein the body comprises an open annular shape.10. An implant according to claim 1 or 2 or 3 or 4 or 5 or 6 wherein thebody comprises at least one rail.
 11. An implant according to claim 1 or2 or 3 or 4 or 5 or 6 wherein the body comprises a wire-form structure.12. An implant according to claim 1 or 2 or 3 or 4 or 5 or 6 wherein thebody is collapsible for placement within a catheter.
 13. An implantaccording to claim 1 or 2 or 3 or 4 or 5 or 6 wherein the body includesat least one cusp sized and configured to permit folding of the bodywithout permanent deformation.
 14. An implant according to claim 1 or 2or 3 or 4 or 5 or 6 wherein the body carries a tissue in-growthmaterial.
 15. An implant according to claim 1 or 2 or 3 or 4 or 5 or 6further including at least one structure appended to the body and beingsized and configured to contact tissue at, above, or below the heartvalve annulus to stabilize the body.
 16. An implant according to claim 1or 2 or 3 or 4 or 5 or 6 wherein the body is sized and configured toextend close to the annulus.
 17. An implant according to claim 1 or 2 or3 or 4 or 5 or 6 wherein the body is sized and configured to extendabove the annulus.
 18. An implant according to claim 1 or 2 or 3 or 4 or5 or 6 wherein the body is sized and configured to contact tissue abovethe annulus.
 19. An implant according to claim 1 or 2 or 3 or 4 or 5 or6 wherein the body is sized and configured to include one portion thatextends close to the annulus and another portion that extends above theannulus.
 20. An implant according to claim 1 or 2 or 3 or 4 or 5 or 6wherein the body is sized and configured to include one portion thatextends close to the annulus and another portion that contacts tissueabove the annulus.
 21. An implant according to claim 1 or 2 or 3 or 4 or5 or 6 wherein the body comprises an elastic material.
 22. An implantaccording to claim 1 or 2 or 3 or 4 or 5 or 6 wherein the body comprisesa plastically deformable material.
 23. An implant according to claim 1or 2 or 3 or 4 or 5 or 6 wherein the body comprises a superelasticmaterial.
 24. An implant according to claim 1 or 2 or 3 or 4 or 5 or 6and further including a retaining element appended to the body andextending over at least a portion of a native heart valve leaflet, therestraining element being shaped to restrain retrograde movement of theheart valve leaflet.
 25. An implant according to claim 1 or 2 or 3 or 4or 5 or 6 and further including a neoleaflet element appended to thebody and occupying the space of at least one native heart valve leaflet,the neoleaflet element being shaped to provide a one-way valve function.26. An implant according to claim 1 or 2 or 3 or 4 or 5 or 6 and furtherincluding a second heart valve treatment element appended to the body toaffect a heart valve function.
 27. An implant according to claim 26wherein the second heart valve treatment element includes means forsupplementing, repairing, or replacing a native heart valve leaflet. 28.An implant according to claim 26 wherein the second heart valvetreatment element includes means for retaining a native heart valveleaflet.
 29. An implant according to claim 3 or 4 or 5 or 6 wherein atleast one of the struts comprises a wire-form structure.
 30. An implantaccording to claim 3 or 4 or 5 or 6 wherein the body and the struts eachcomprises a wire-form structure.
 31. An implant according to claim 3 or4 or 5 or 6 wherein at least one of the struts is collapsible onto thebody.
 32. An implant according to claim 3 or 4 or 5 or 6 wherein atleast one of the struts carries a tissue in-growth material.
 33. Animplant according to claim 3 or 4 or 5 or 6 wherein at least one of thestruts carries a structure sized and configured to increase a surfacearea of contact with tissue at, above, or below the annulus.
 34. Amethod for reshaping a heart valve annulus comprising the steps ofintroducing an implant as defined in claim 1 or 2 or 3 or 4 into aheart, and displacing tissue to reshape the heart valve annulus bylocating the body of the implant as defined in claim 1 or 2 or 3 or 4near or within a heart valve annulus.
 35. A method according to claim 34wherein the introducing step comprises using an open heart surgicalprocedure.
 36. A method according to claim 34 wherein the introducingstep comprises using a surgical procedure in which the implant iscarried within a catheter.
 37. A method according to claim 34 whereinthe introducing step comprises using an intravascular surgicalprocedure.
 38. A method according to claim 34 wherein the displacingtissue step comprises tethering the body of the implant as defined inclaim 1 or 2 or 3 or 4 to at least one wire while locating the body nearor within a heart valve annulus.
 39. A method for reshaping a heartvalve annulus comprising the steps of introducing an implant as definedin claim 5 into a heart, and applying tension to reshape the heart valveannulus by locating the body of the implant as defined in claim 5 in netcompression at or near a heart valve annulus with the struts in contactwith and applying tension to tissue near or within the heart valveannulus.
 40. A method for reshaping a heart valve having an annulus andleaflet commissures comprising the steps of introducing an implant asdefined in claim 6 into a heart, and applying tension to shape andtension the heart valve annulus for leaflet coaptation by locating thebody of the implant as defined in claim 6 in net compression at or nearthe leaflet commissures with the struts in contact with and applyingtension to tissue at or near the leaflet commissures.
 41. A methodaccording to claim 39 or 40 wherein the introducing step comprises usingan open heart surgical procedure.
 42. A method according to claim 39 or40 wherein the introducing step comprises using a surgical procedure inwhich the implant is carried within a catheter.
 43. A method accordingto claim 39 or 40 wherein the introducing step comprises using anintravascular surgical procedure.
 44. A method according to claim 39 or40 wherein the applying tension step comprises tethering the body of theimplant as defined in claim 5 or 6, respectively, to at least one wirewhile locating the body in compression at or near a heart valve annulus.